Notebook Ruler Square – Straight Edge for Squaring Rulers & Stationery (3D Printed)

Get a crisp straight edge for squaring up rulers and other stationery. This small 3D printed square sits under your notebook and gives you a precise, stable corner to align rulers, T-squares, and drafting tools against — no more sliding pages or crooked lines. Great for bullet journaling, note-taking, and drafting. Durable PETG build, lightweight, fits just about any notebook or journal. Made to order in the USA by JohnnyGod3D.